The decision by Kosovo’s parliament to form a national army was described by the UN Peacekeeping chief on Monday as having “further deteriorated relations between Belgrade and Pristina,” which, he said, have been strained for some time.

Jean Pierre Lacroix, head of the Department of Peacekeeping Operations (DPKO) was briefing the Security Council on recent developments that have heightened tensions between Serbia and Kosovo, which became embroiled in conflict in the late 1990s, when Kosovo made a bid for independence.

Mr. Lacroix began his briefing, by pointing to November 21, when Kosovo announced new tariffs on goods imported from Serbia and Bosnia, raising them from ten to 100 percent. In reaction, Mayors of four Kosovo Serb-majority regions of northern Kosovo, announced their resignations, and the parliaments of their municipalities cut off official communications with the capital, Pristina.

Serbia, for its part, announced that it would only take part in European Union-facilitated talks with Kosovo if the tariff hike was reversed.

This was the tense backdrop, said Mr. Lacroix, for Kosovo’s adoption of three laws that provide for “substantial changes” to the mandate, role and strength of the Kosovo Security Force. The Government’s intentions were clarified in a statement which announced the country’s right to have “an army, a multi-ethnic and professional force built under the highest NATO standards.”

Serbia characterized the move by Kosovo as an act of “political aggression” and called on KFOR, the NATO-led peacekeeping force – which was set up following a Security Council resolution and is responsible for establishing a secure environment in the country – not to allow any kind of “Kosovo Army” to operate. According to media reports, Serbia has warned that the creation of such an army would violate a UN resolution that ended Kosovo’s war of independence from Serbia.

On Friday, UN chief António Guterres “noted with concern” Kosovo’s adoption of the draft laws to strengthen its Security Force, reiterating that only KFOR has the responsibility to ensure a safe and secure environment in the country, and calling on all parties to exercise restraint and refrain from any actions that could raise tensions.

In his Monday briefing, Mr. Lacroix said that it was crucial that the two countries avoid any steps that could further worsen the situation, and urged them to “find ways to re-engage in the dialogue aimed at the normalization of their mutual relations.” The UN Mission in Kosovo (UNMIK), he added, is working closely with KFOR, and focusing on inter-community trust building, which is “essential for the long-term normalization of relations between Belgrade and Pristina.”